MDCT findings of denim-sandblasting-induced silicosis: a cross-sectional study

Abstract

Background: Denim sandblasting is as a novel cause of silicosis in Turkey, with reports of a recent increase in cases and fatal outcomes. We aimed to describe the radiological features of patients exposed to silica during denim sandblasting and define factors related to the development of silicosis.

Methods: Sixty consecutive men with a history of exposure to silica during denim sandblasting were recruited. All CT examinations were performed using a 64-row multi-detector CT (MDCT). The nodules were qualitatively and semi-quantitatively analyzed by grading nodular profusion (NP) on CT images.

Results: Silicosis was diagnosed radiologically in 73.3% of patients (44 of 60). The latency period (the time between initial exposure and radiological imaging) and duration of silica exposure was longer in patients diagnosed with silicosis than in those without silicosis (p < 0.05). Nodules were present in all cases with centrilobular type as the commonest (63.6%). All cases of silicosis were clinically classified as accelerated and 11.4% had progressive massive fibrosis (PMF). Mild NP lesions were the most prevalent in all six zones of the lung. The NP score was significantly correlated with the duration of silica exposure, the latency period, presence of PMF, and pleural thickening. Enlarged lymphadenopathy was present in 45.5% of patients.

Conclusions: The duration of exposure and the latency period are important for development of silicosis in denim sandblasters. MDCT is a useful tool in detecting findings of silicosis in workers who has silica exposure.

Figure 1

The areas under the curve (AUC) for the duration of exposure to denim sandblasting (line) and the latency period (dashed line) were 0.703 and 0.683, respectively.

Figure 2

a, b - Diffuse centrilobular nodules on 5-mm-thick reconstructed axial (a) and coronal maximum intensity projection (MIP) images (b) in a 24-year-old man who worked as a denim sandblaster for 48 months.

Figure 3

a, b - Coronal (a) and sagittal (b) reconstructed computed tomography images showing the predominance of nodules located in the upper lobes and peripheral regions of the lungs in a 29-year-old man who worked as a denim sandblaster for 20 months.

Figure 4

a, b - PMF and bands leading to parenchymal distortion in adjacent regions in both upper lobes of the lung are apparent on axial (a) and coronal (b) CT sections of a 27-year-old man who worked as a denim sandblaster for 48 months.

Figure 5

CT images of a 29-year-old man who worked as a denim sandblaster for 20 months. Paratracheal and left side hilar lymph nodes with central and eccentric calcification are shown.

Figure 6

The right-sided pleural thickening in a 23-year-old man who worked as a denim sandblaster for 36 months. (a: mediastinal window, b: lung window).

Figure 7

Mild dilatation in the bronchus of the upper lobes and thickening of the bronchial wall is apparent in a 27-year-old man who worked as a denim sandblaster for 20 months.